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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                %p <strong>Click</strong> a button to activate its animation.
.btn-container
  %button.btn.btn--shockwave.is-active
    Shockwave
  %button.btn.btn--jump
    Jump
  %button.btn.btn--pulse
    Pulse
  %button.btn.btn--blink
    Blink
  %button.btn.btn--wiggle
    Wiggle
  %button.btn.btn--wut
    Hatching Alien
!

CSS 

              
                $spacing__base: 1.6rem;
$easing: cubic-bezier(.33,.33,.33,1);
$background:  darken(#daecf3, 12);
$gradient_end: darken(#D7EDEC, 8);

@mixin afterBg {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  border-radius: 50%;
}

body {
    max-width: 600px;
    margin: $spacing__base * 3 auto;
    background: $background;
    font-family: tahoma, helvetica neue, helvetica, arial, sans-serif;
    background: -webkit-linear-gradient(to right, $background, $gradient_end);
    background: linear-gradient(to right, $background, $gradient_end);
    text-align: center;
   
}

.btn-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-around;
}

.btn {
  width: $spacing__base * 4;
  line-height: $spacing__base * 4;
  background: #fff;
  border-radius: 50%;
  text-align: center;
  margin: $spacing__base;
  font-size: 0.8rem;
  border: none;
  padding: 0;
  position: relative;
  // MAKE SURE YOU HAVE AN ACCESSIBE FOCUS STATE
  outline: none;
}

// Shockwave
.btn--shockwave.is-active {
  animation: shockwaveJump 1s ease-out infinite;
  
  &:after {
    @include afterBg;
    animation: shockwave 1s .65s ease-out infinite;
  }
  
  &:before {
    @include afterBg;
    animation: shockwave 1s .5s ease-out infinite;
  }
}

@keyframes shockwaveJump {
  0% {
    transform: scale(1);
  }
  40% {
    transform: scale(1.08);
  }
  50% {
     transform: scale(0.98);
  }
  55% {
    transform: scale(1.02);
  }
  60% {
    transform: scale(0.98);
  }
  100% {
    transform: scale(1);
  }
}

@keyframes shockwave {
  0% {
    transform: scale(1);
    box-shadow: 0 0 2px rgba(0,0,0,0.15), inset 0 0 1px rgba(0,0,0,0.15);
  }
  95% {
    box-shadow: 0 0 50px rgba(0,0,0,0), inset 0 0 30px rgba(0,0,0,0);
  }
  100% {
    transform: scale(2.25);

  }
}

// JUMP
.btn--jump.is-active {
  animation: .4s jump ease infinite alternate;
}

@keyframes jump {
  0% {
    transform: scale(1);
    box-shadow: 0 1px 2px rgba(0,0,0,.15);
  }
  100% {
    transform: scale(1.05);
    box-shadow: 0 4px 20px rgba(0,0,0,.1);
  }
}

// PULSE
.btn--pulse.is-active {
  background: transparent;
  
  &:after {
    @include afterBg;
    background: #fff;
    animation: pulse 0.4s ease infinite alternate;
    z-index: -1;
  }
}

@keyframes pulse {
  0% {
    transform: scale(1);
    box-shadow: 0 2px 2px rgba(0,0,0,.2);
    border-radius: 50%;
  }
  100% {
    transform: scale(1.05);
    box-shadow: 0 2px 2px rgba(0,0,0,.2);
    border-radius: 45%;
  }
}


// BLINK
.btn--blink.is-active {
  background: transparent;
  
  &:after {
    @include afterBg;
    background: #fff;
    animation: blink 1.33s ease-out infinite;
    z-index: -1;
  }
}

@keyframes blink {
  0% {
    opacity: 1;
  }
  20% {
    opacity: .5;
  }
  100% {
    opacity: 1;
  }
}

// Wiggle
.btn--wiggle.is-active {
  animation: 1s wiggle ease infinite;
}

@keyframes wiggle {
  0% {
    transform: rotate(-3deg);
    box-shadow: 0 2px 2px rgba(0,0,0,.2);
  }
  20% {
    transform: rotate(20deg);
  }
  40% {
    transform: rotate(-15deg);
  }
  60% {
    transform: rotate(5deg);
  }
  90% {
    transform: rotate(-1deg);
  }
  100% {
    transform: rotate(0);
    box-shadow: 0 2px 2px rgba(0,0,0,.2);
  }
}


// WUT
.btn--wut.is-active {
  animation: 1s fullRotation ease infinite;
  
  &:before {
    @include afterBg;
    background: #fff;
    animation: wutBefore 0.8s .4s ease-out infinite;
    z-index: -1;
  }
  
  &:after {
    @include afterBg;
    background: #fff;
    animation: wut 0.8s ease-out infinite;
    z-index: -1;
  }
}

@keyframes fullRotation {
  0% {
    transform: rotate(-3deg) scale(1) translate3d(0,0,0);
  }
  20% {
    transform: rotate(50deg)  translate3d(0,5px,0);
  }
  40% {
    transform: rotate(-15deg) scale(1.1) translate3d(0,8px,-5px);
  }
  60% {
    transform: rotate(5deg) translate3d(5px,-8px,-80px);
  }
  90% {
    transform: rotate(-1deg) translate3d(0,0,0);
  }
  100% {
    transform: rotate(0);
  }
}

@keyframes wut {
  0% {
    border-radius: 50%;
    transform: skew(0) translate3d(0, 0px, 0px);
  }
  10% {
    transform: translate3d(0, -10px, 0);
  }
  50% {
    border-radius: 50%;
  }
  80% {
    border-radius: 30%;
    transform: translate3d(20, 10px, 20px);
  }
  100% {
    border-radius: 50%;
    transform: skew(0) translate3d(0, 0px, 0px);
  }
}

@keyframes wutBefore {
  0% {
    border-radius: 50%;
    transform: translate3d(0, 0px, 0px);
  }
  10% {
    transform: translate3d(-10px, 10px, 0);
  }
  70% {
     border-radius: 50%;
  }
  80% {
    border-radius: 30%;
    transform: translate3d(-20px, -10px, -20px);
  }
  100% {
    border-radius: 50%;
    transform: translate3d(0, 0px, 0px);
  }
}
!

JS 

              
                document.addEventListener('click', click);

function click(e) {
  let el
  
  el = e.target
  
  if (el !== e.currentTarget) {
    if(el.nodeName === 'BUTTON') {
      
       if(el.classList.contains('is-active')) {
         el.classList.remove('is-active')
       } else {
         el.classList.add('is-active')
       }
    }
  }
  event.stopPropagation()
}
!
999px

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